Sharpening device.



No. 648,090. Patented Apr. 24, |900.

W THOMPSON SHABPENINB DEVICE.

(Appl t dSept 6 1899) (No Model.)

W/ TNE SSE S anion,

l WILLIAM THOMPSON, OF STRATFORD-UPON-AVON, ENGLAND.

SHARPENING DEVICE.

SPECIFICATION forming part of Letters Patent N o. 648,090, dated April 24, 1900.

Application filed September 6,1899. Serial No. 729,597. (No model.)

those skilled in the art to which it appertains to make and use the same.

This invention relates to knife-Sharpeners, and has more particular reference to a device of this class by means of which a serrated edge may be formed upon a cutting-tool. It is well known that a cutting edge of serrated or irregular formation is vastly more effective in operation than a plain straight cuttingV edge. To produce serrated cutting edges, I employ asharpenin g device which is fully disclosed in the following specification, of which the accompanying drawings form a part, in which like reference characters denote like parts in the several views, and in Which- Figure l is a perspective view of a sharpening device constructed according to my invention, showing a knife in the operation of receiving a serrated edge; Fig. 2, an enlarged side view of a portion thereof; Fig. 3, an enlarged transverse section of a portion thereof, and Figs. 4 and 5 are respective views lof modified forms thereof.

Referring more particularly to the drawings, I have shown at 6 a base or block upon which is secured, by means of screws 7, a yokeshaped support S, in the arms of which is journaled, by means of bearings IO, a cylindrical block 9.. The block 9 is provided with a metal sheath or sleeve 12, secured thereto by means of screws I3 and provided with longitudinal serrations lawhich are formed similarly to the teeth of a file and finished similarly to a file.

In the operation of the form of device described the knife or other tool l5 is previously given a cutting edge by the application of any ordinary or preferred sharpening instrument, and said edge is then brought to bear upon the serrated sleeve l2 and is moved over the saine to rotate it upon its bearings, and

said motion will serrate the cutting edge of the tool l5.

In Fig. 4 I have shown a modified form of the device described, in which the bearings IO (shown in Figs. l, 2, and 3) are fitted into handles 16; but the remaining parts are all unaltered in construction and arrangement.

In Fig. 5 I have shown a still further modified form of construction in which the said bearings 10 are inserted in the arms of a yokeshaped support 17, provided with a single handle 1S but the remaining parts are all unaltered in construction and arrangement.

The modification shown in Fig. 4 is 'used in connection with a tool which is firmly held by a vise or other clamping device, the handles being grasped in both hands and the serrated sleeve l2 passed over the cutting edge of the tool, causing the serration of the said cutting edge.

The modification shown in Fig. 5 is grasped in one hand by the handle I8, and the serrated sleeve 12 is passed over the cutting edge .of a tool held in the other hand, causing the serration of the said cutting edge.

It is evident that many changes may be made in the construction and arrangement of the elements of my invention without departing'from the spirit thereof, and I claim all such as come within the scope thereof.

Having fully described-my invention, I claim as new and desire to secure byLetters Patent- I. The herein-described improved implement, comprising a sharpening device consisting of a cylindrical block or body provided with a longitudinally-serrated surface, said block or body being journaled in a yokeshaped support provided with a handle, substantially as shown and described.

2. As an improved article of manufacture, a sharpening device consisting of a cylindrical block or body provided with a separate serrated metal sleeve secured thereto by fastening means, said block or body being provided with end bearings, and a yoke-shaped support in which said bearings are fitted, substantially as and for the purpose set forth.

3. The herein-described improved implement, comprising a cylindrical block or body my invention I have signed my name, in presprovided Withaseparate serrated meta] sleeve ence of the vsubscribing Witnesses, this 24th 1o secured thereto by independent fastening del day of August, 1399. Vices, said block or body being rovded with l i end bearings, and a yoke-shaped support in 1 VILLAM THOMPSON which said bearings are fitted, said support being provided with n handle.

In testimony that I claim the foregoing as rimesse/s:

FREDERICK MARSHALL BURTON., GRAHAM TREVASKIS COX. 

